Heating device



Nov. 5, 1935. G. F. KOTRBAII'Y 2,019,913

HEATING DEVICE Fild F'eb. 4, 1932 3 Sheets-Sheet 1 FIG- INVENTOR GuYFKoTRBA-rY A TTORNEVS' I Nov. 5, 1935. G. F. KOTRBATY 2,019,913

HEATING DEVICE Filed Feb. 4. 19:2 5' Sheets-Sheet 2 4 '3 'A I I r INVENTOR 6W By 1 Guy l. KOTRBA-I-Y I n llTTfQjt F. KOTRBATY 2,019,913

HEATING DEVICE Nov. 5, 1935.

'Filed Feb. 4, 1932 3 Sheets-Sheet 3 FIGJZ. new

GuYEKoTRBATY type heaters'involving the use of heater elements broken away to show the heating element Patented Nov. '5, 1935 UNITED STATES PATENT owl-cs Guy F. Kotrbaty, Astoria, N. Y.

Application February 4, 1932, Serial No. 590,847

13 Claims.

This invention relates to improvements in heating devices, and more particularly to an improved convection type heater and heating element and process for making the same.

Hitherto, in the manufacture of convection embedded in insulating cements and encased in metallic tubes or other containers, it has been proposed to apply heat radiating devices such as sheets of metal perforated or otherwise conformed to fit the heater unit assembled. Such installations are costly to manufacture due to the number of parts required and due further to the fact that various size heater assemblies require dlfierent die setups and such assemblies are not adapted for continuous manufacture but require hand assembly operations throughout.

It is an object of this invention to provide an improved heater element having a selfcontained radiating section as well as an improved process for manufacturing same.

It is a further object of this invention to provide an improved combination heater element and radiating device which is susceptible of manufacture by automatic machinery in any desired length and having any desired electrical and thermal characteristics.

Yet another object of this invention is the provision of an improved convection type radiator unit adaptable for use with electricity, steam or other type of heating means.

A further object of this invention is the provision of an improved radiating member for heating systems including a section adapted to contain a heating substance anda plurality of suitably configuredassociated integral sections adapted to receive heat from the first section and to serve as radiating members.

These and other desirable objects and advantages of the present invention will be described in the accompanying specification and illustrated inthe drawings, certain preferred embodiments being disclosed by way of example only, for, since the underlying principles may be incorporated in other specific constructions, it

is not intended to be limited to those here shown, except as such limitations are clearly imposed by the appended claims.

In the drawings like numerals refer to similar parts throughout the several views, of which Fig. 1 is a front elevation partly in section of an improved vaned heating member, parts being sulating beads;

Fig. 2 is a viewsimilar to Fig. 1 showing the vaned portion fluted and the heating element insulated by suitable insulating yam;

Fig. 3 is a compound vaned heating member showing the heating element disposed longitudinally of the center thereof;

Fig. 4 is a view similar to Fig. 3. showing a pair of parallel heating sections;

Fig. 5 is a view similar to Fig. 1, showing a rectangular heating element sheath;

Fig. 6 is a view similar to Fig. 3, showing the 10 application of a rectangular heating element sheath;

Fig. 7 is a top plan view ota skelp formed with heating sections at both edges thereof and partly I slit diagonally to show the method of formation 15 of a pair of separate heating members;

Fig. 8 is an elevation of a heating member formed from the skelp shown in Fig. '1; Fig. 9 is an elevation of a section of a heating member made'up from the material shown in 20 Fig. 8;

Fig. 10 is an elevation of a helical heating member made by twisting the construction shown in Fig. 1 about a mandrel;

Fig. 11 is a broken vertical section of the structure shown in Fig. 10;

Fig. 12 is a view similar to Fig. '1 showing the use of'a unilateral vaned heating member with cut-out portions between the vanes to be arranged in parallel; 1 v

Fig. 13 is a modification of the structure shown generally in Fig. 1 in which the heating element sheath portion is provided with a pair of abutted vanes; I

- Fig. 14 is a further modification of. the structure shown in Fig. 13 in which the vanes are separated and slotted to provide air space therebetween;

Fig. 15 is a compound vaned heating element composed of a pair of opposed centrally channeled members; g

Fig. 16 shows a heating member having a central heating element receiving channel and an opposed channeled strip co-acting therewith to forma housing for the heating member;

Fig. 1'7 is a view similar to Fig. 16 showing the separate channel members crimped in place;

Fig. 18 shows the heat element sheathing memher with unilateral vanes and a further vaned member associated therewith; 50

Fig. 19 shows a heating element of the type shown in Fig. 1 convoluted to form an enlarged heating member;

' Fig.2!) shows a double convoluted heating member supported in a suitable cabinet;

Fig. 21 is a front elevation of a convoluted heating member having parallel heat radiating sections: and 1 r Fig. 22 shows a heating member of the type shown in Fig. 19 adapted for the use of fluid heating agents. L

Referring more specifically to the drawings, the improved heating member of the present invention comprises a heat element supporting or engaging section or sheath Ill, together with a lateral vaned member ll formed integral with the sheath section. A resistance element 12 of any desired sizeand composition may be provided with suitable insulating members ll of porcelain,

steatite, 'sillimanite, lavite, soapstone. Dyrex glass,

magnesia, mica, or other insulating elements.

The wire may be insulated by dipping or passing through a suitable insulating composition until the requisite thickness is secured. Phenol and other like insulating materials may be used, depending upon the operating temperature and dielectric design of the unit. These insulating members II are so configured and arranged as to permit the resistance member I! to be threaded therethrough and to support said member uniformly and evenlyspaced from the walls of the ,section It, thus providing an even heating of the latter, together with a uniform withdrawal of the heat therefrom by the radiating vaned section ll.

The heating element may be coated in any continuous or intermittent clip process with a suitable insulating material, depending upon the marimum operative temperature to which it is to be subjected during use. Ordinary cements or maximum temperature to be expected from the unit will rarely exceed 400' 7., which condition permits the use of a relatively thin insulating coating about the heating element proper. The actual thickness of the wall, as may be expected, will vary according to the electrical characteristics of the current used and the dielectric strength required. for the material. Where higher temperatures are to be attained the dimensions of the devicewill besuitably varied. In

all cases the relative size of the different parts 'will be governed only by the temperature wanted and the voltage imposed.

While the vaned section II may be plain in configuration,- its area may be appreciably increased by folding or scalloping, or other means.

1 as indicated generally at It in Fig. 2. In place of a straight wire resistance member II, a ribbon It may be used, as shown in Figs. 5 and 6, or the resistance member I may be coiled about an asbestos form l'l and the combination formed about a suitable flexible mandrel or arbor |l.

'Where it is desired to increase the heat radiating surface of the varied sections of the heating This construction proand along the sides thereof, the vane may be curved to form a deflector, as indicated generally. at Ila in Fig.1.

Where it is desired to provide for the utilisation of a plurality of heats in a given heating member, the construction shown in Fig. 4 is particularly suited. This comprises a plurality of parallel heat element supporting sheaths 20, together with associated vane sections 2|. The heating elements may comprise resistance elements I! wound with asbestos yarn 22. By providing a plurality of heating elements, these latter maybe connected through suitable switching mechanisms, either in series to give a low heat, singly to give medium heat, and multiple to give maximum heat. Any suitable switchingmechanism may be provided to give the desired connectlons between the elements and the heating In the construction shown in Figs. 5 and 8, the heat element supporting sheath section comprises a rectangular section II formed in any suitable manner. The'ribbon resistance element II may be covered with asbestos yarn, mica or any other suitable material, designated generally by the numeral 24.

While a varietyof insulating materials in various forms have been shown anddescribed as suitable for the purposes of this invention, it will also be appreciated that the resistance elements may be suitably spaced in their respective sheaths and provided with an insulating cement, any forming or bending of the composite being accomplished before the cement is permitted to harden.

Where it is desired to form the improved heatingmember of the presentinvention into hellcal or other shapes, whether of round, polygonal or square cross section, the members shown in Figs. 7, 8 and 9 are of particular interest.

Referring more particularly to Fig. 'l, the skelp is shown as formed with a pair of sheath sections Iii formed on the edges thereof, being provided with any suitable heating arrangement, not shown. The intermediateskelp section is suitably divided by cutting or forming into. a plurality of vaned sections 15 which are adapted to be separated as the material is formed so as to provide two separate and complete heating members having triangular vaned sections formed integrally with the heating element sheath section. These members may be used in any desired configuration, and, as shown more particularly in Fig. 9, they maybe so bent that the edges of the triangles formed by the members I! may. be abutted to form substantially square. vanes centrally of a continuous heating element sheath, which construction may be continued to any desired length to provide a plurality of parallel heating vaned members. This general effect may also be secured by slotting the vanes andremoving portions therefrom to provide gaps or spaces 28 between successive vanedsections :21, the sheath element It being bent or formed so as to align the members 21 in parallel, as shown in Fig. 12. I Where a helical type of heating element is de- 7 sired, the element may be formed so that the vaned portion II is reduced slightly along its periphery in order to provide the additional metal surface to permit the desired convolution to be made. All of the members heretofore described may be made by rolling in suitable machines, the constructions being subjected to cold roller forming. The heating elements, with their associated insulated covers and supports, may be introduced into the sheath sections before the latter are closed in place, and the latter may thereafter be suitably flnished, as by crimping, welding, brazing or soldering, to provide fluidtight sections, where desired.

In the constructions shown in Figs. 13 to 18, inclusive, the sheath section ll may be'provided with a heat radiating vaned section or sections, and in such cases the skelp may be channeled centrally and folded over so as to provide heat radiating vanes 30, which are abutted. These vanes may be secured together, if desired. If the vanes 30 are spaced apart to form a space II therebetween the bottom portions of the vanes may be slotted, as indicated at 32, to provide for the flow of air from the exterior of the vanes inwardly to the space 3|, where it may serve to remove heat from the inner surfaces of the vanes.

In the construction shown in Fig. 15, the skelp may be centrally channeled, as indicated at 35, and a pair of such members abutted with their vaned sections 36 aligned so as to form a central channel 31, which is enclosed or formed by the opposed-channel sections II. These composite members may be secured together in any suitable manner, by crimping, welding, brazing, etc. or, as indicated in Fig. 16, one of the members may have its vaned sections I! considerably reduced, as indicated at 36A. and secured to the cooperating member by means of rivets 30, although the members may be secured together by spot welding or in accordance with any of the other methods previously set forth.

As shown in Fig. 17, the varied sections 36 may be crimped, as indicated at 39, to secure the sections "A of the cooperating member in place to form the channel or tube section 31.

In the construction shown in Fig. 18, the sheath section It of any suitable configuration, is provided with parallel flange portions 40' extending laterally for a relatively short distance, and a separate vaned member ll is disposed therebetween and secured thereto in a suitable manner by means of rivets 42, or by spot welding, brazing or soldering.

In the construction shown in Fig. 19, the heating element is so configured and arranged that the vane is folded upon itself a number of times. the fold being indicated generally at II to provide a plurality of parallel heat radiating sections through which air or other fluid is adapted to freely pass. By fluting or thus folding or forming the continuous heating member a maximum of heating surface is enabled to be encompassed within a given space so that the heating member of the present invention, although adapted to be formed in continuous lengths, may be tailored to fit any desired condition and to give a desired heat. This may be accomplished not only by increasing the heat radiating surface, but, of course, by suitably choosing the heating elements so that their characteristics will meet with the varying voltages and resistances required for the particular electrical purposes.

Thus it will be seen that to produce the B. t. u.

radiation requirements for any given service it will be sufficient to figure out the heating vane surface required for a given available current, or to meet the heating element requirements desired, and the improved heating member may be thereafter configured to any desired shape or form to fit the design imposed.

The novel elements of the present invention are particularly adapted for use in convection 3 type radiator cabinets, designated generally by the numeral Na and which comprises a closed box having an open bottom, the front of the box being provided with a grille-work ii at the top, which is so designed with respect to the 5 height of the box and the aperture area that the box provides a suitable stack for the heating element mounted on the supports N. A deflector vane I may be formed inside the cabinet and at suitable height therein to deflect the heated air forwardly through the grille. The aperture area of the grille system should preferably be .about 70 per cent of the total grille area. The

heating member may be serviced by suitable means comprising a core I connected to a switch member if of any desired construction, suitable connections being made to the resistance elements.

The supporting member ill may be supported on the .cabinet in any desired manner, as by means of brackets or supported in the end walls by bolts and nuts, as shown. By passing the supports through the vanes II, the latter are prevented from buckling and forming any undesirable movement within the case, although without in any way affecting their emcieney as heat radiating elements.

Referring more particularly to Fig. 21, the cabinet may be provided with a cover 10 which is raised up from the body thereof, the said cover being provided with depending flanges II which extend down and below the upper edge 12 of the cabinet walls to provide a space It between the cover and the said cabinet, the member ll serving to deflect the heated air downwardly and outwardly from the cabinet. The covers may be supported on the frame in any suitable manner, as by means of brackets I3. By providing a raised cover having a depending flange whose bottom edge falls below the upper edge of the box. thenecessity of forming a grille in the cabinet proper is obviated, thus permitting a very desirable saving in cost of manufacture without sacrificing any heating efliciency of the device. 5

While the novel improvements of the present invention have been described with particular reference to the use of electrical heaters of the convection type, it will be understood that the improved vaned heating element is susceptible of use with heating fluids generally. As shown in Fig. 22, the tubular section 80 may be of any desired size and shape and may be threaded at its ends, as indicated at II. The heat radiating vane 82 may be formed integrally, as indicated, the whole having been formed from a piece of skelp and a suitable seam 83 formed to provide a fluid and pressure type joint. The seam may be made in any suitable manner, but for fluid type joints adapted to withstand the desired on pressure welding or brazing is recommended. A suitable seam welding machine may be made use of to form the seam as the section 80 is rolled during formation. The size of the section IQ of the composite member will, of course, vary aco5 cording to the material which is to be used as a heating fluid. Where steam or hot water is to be used, it will be of fairly large cross section. Where oil or mercury or other fluids are to be used, the cross section will be reduced accord- 7o ingly.

It will now be appreciated that there has been provided an improved novel heating member comprising heat element-enclosing sheath sections and an associated heat radiating member formed integrally from a suitable piece 01' material such as a .skelp and by any continuous process, such as rolling, stamping, welding, and the like. Where the sheath and vane are formed integrally, the sheath may be made fluid tight by closing the seam, as by crimping or seam welding or brazing or soldering, according to the pressure and heat which the construction must withstand. The improved heating element may be formed in continuous lengths and cut to a desired size, either before or after being formed to any desired shape. The heating elements may be automatically fltted in place during the forming of the sheath and secured thereto during said process. Thesaid heating elements are so designed as to give a desired heat for a given purpose without involving any danger of overheating of the device.

Due tothe rigidity imparted to the device by the tubular sections, the novel heating units may be made up oi relatively thin metal stock without in any way impairing the structural eillciency of the device and at the same time assuring a desired increase in heat radiating eiliciency due to the high heat conductivity of the thin metal sheets. Owing to the high heat conductivity of sheet metals generally the conduit section may be relatively small with respect to the overall surface of the heat radiating section, which latter will extract the heat rapidly from the heat supplying section and impart it to the circumambient air or other fluid contacted therewith.

Owing to the fact that the heat radiating surface of the vaned member is coextensive in length with the heating conduit or sheath it will be appreciated that there will be an even with drawal of heat from the sheath member throughout its length, thereby insuring uniform heating of the entire surface of the vaned member for each quantity of heat handled by the unit. This improved construction further prevents the building up of excessive quanta of heating values in isolated portions of the device as often happens in heat radiating members made of cast metals of relatively lower heat conducting capacity. although of somewhat higher heat storing capacity.

It will thus be appreciated that by providing a substantially infinite heat radiating surface with respect to the area of the heat supplying portion of the member, optimum and rapid heat removal is provided and a maximum of contact with the effective portion of the heating area is provided for the air or other fluid used as a heating medium.

The improved device of the present invention.

as intimated, may be made from a wide varietyof sheet metals including aluminum, copper, tin, brass, bronze, nickel, steel, iron or other metals, as well as glass, pyrex, porcelain, china and other vitreous materials. Care should be taken to choose the proper metal or other material according to the heating element or fluid to be used and the operating conditions to which it is to be subjected.

It will now be appreciated that there has been provided an improved composite heating member which is adapted for use with electricity, steam.' hot water, oil or metallic heating fluids, and which is characterized bya substantially continuous sheet metal construction adapted to be formed in automatic machines and to be conformed to suit any desired purpose.

While certain novel features of the invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated andin its operation may be made by those skilled in the art without departing from the spirit of 5 the invention.

What is claimed is:

1. An improved heating device comprising a continuous heating section oi generally tubular shape, an insulated heating element in said section and a heat radiating vane formed integral with said heating section forming a single unitary sheath therefor and-coextensive therewith, the said heating section and associated parts being adapted to be bent upon itself whereby to form a plurality of heat radiating segments in a single unit.

2. An improved heating element comprising a heating section of generally tubular shape, an insulated heating member in said section and a heat radiating vane formed integral with said heating section and coextensive therewith, said vane having alternate cut-out portions and the heater being so configured and arranged as to form a series of parallel vane sections integral with the heater tube, but disconnected from each other.

3. An improved heating element comprising a heating section of generally tubular shape, an insulated heating member in said section and a heat radiating vane formed integral with said heating section and coextensive therewith, said vane being serrated so as to permit the heater unit to be bent about the serrations whereby to form a series of plate-like members surrounded by the continuous heater tube.

4. An improved heating device comprising a single elongated heating section of generally tubular shape, a flexible heating element in said section and a .heat radiating vane formed integrai with said heating section forming a single sheath therefor and coextensive therewith, the said heating section and associated parts being adapted to be bent on themselves a plurality of times to form a series of parallel heat-radiating segments.

5. An improved heating device comprising a continuous elongated heating section of generally tubular shape adapted to be bent upon itself a plurality of times and formed from a continuous skelp, a flexible heating element in said section and a heat radiating vane formed integral with said heating section forming a single sheath therefor and coextensive therewith. said flexible heating element comprising a resistance element and an insulated cover of asbestos.

6. An improved heating device comprising a continuous elongated heating section of generally tubular shape adapted to be bent upon itself a plurality of times and formed from a continuous skeip, a flexible heating element in said section, a heat radiating vane formed integral with said heating section forming a single sheath therefor and coextensive therewith, said flexible heating element comprising a resistance element and a plurality of juxtaposed insulated supports strung on said element.

7. An improved heating device comprising a continuous elongated heating section of generally tubular shape adapted to be bent upon itself a plurality of times and formed from a continuous skelp, a flexible heating element in said section. a heat radiating vane formed integral with said heating section forming a single sheath therefor and coextensive therewith, said flexible heating element comprising a mandrel and a coiled reslstance element mounted on an insulating material and wound about said mandrel.

8. An improved heating device comprising a central skelp portion, heating sections formed on the edges of said skelp portion and integral therewith, said skeip portion being adapted to be divided to form a plurality of separate heating devices, each of said heating devices having a separate heating section, the said skelp portion and associated heating devices being formed of .unitary material and being further adapted to form unitary single sheaths tor the respective heating devices.

9. An improved heating element comprising a continuous, non-jointed tubular heating portion, and a heat radiating vane section formed integral with said tubular section and laterally thereof, the said tubular section forming a unitary sheath for heating medium disposed therein.

10.- An improved heating element comprising a continous, non-jointed tubular heating portion, a plurality of heat radiating vanes formed integral with said tubular section and coextensive therewith, the said tubular section forming a unitary sheath for heating medium disposed therein.

11. An improved heating member comprising a heating portion and heat radiating vanes formed integral with said heating section and coextensive therewith, said vanes being spaced in parallel relation and provided with slots, adjacent said heating section.

.12. A composite heating member having a heating section comprising a pair of opposed channel sections, heat radiating vanes integral with and extending laterally from said channel section, said vanes and channel sections being abutted to form a continuous tubular section with heat radiating vanes continuous therewith, one of said channels having heat radiating vanes laterally thereof and coextensive therewith and the other of said channels having lateral flanges adapted to be abutted to the first named vanes whereby to form a heating channel, said members being.adapted to be permanently secured to make a fluid tight channel.

13. In an electric heater having a radiator cas-, ing, and means within the casing for supporting a heater and causing air to flow through the casing in contact with the, heater, the improvement comprising a continuous heating element bent upon itselI to form a plurality of heat radiating sections, said heating element having at least one heating section and a heat radiating section integral therewith, and heating means disposedin the heating section,-the said heat radiating section forming a-singie unitary sheath for the heating means disposed therein.

- GUY F. KOTRBATY. so 

